Compositions containing a quinoxaline-5,10-dioxide and method of using same

ABSTRACT

1,2-DIHYDRO-2-OXO-4-AMINOPYRIMIDO(4,5-B)QUINOXALINE-5,10DIOXIDES DEMONSTRATE ANTIMICROBIAL ACTIVITY AND CAN BE USED AS SUCH OR IN COMPOSITIONS FOR COMBATTING INFECTIONS AND IN IMPROVING FEED EFFICIENCY. The compounds, of which 1,2-dihydro-2oxo-4-dimethylaminopyrimido(4,5-b)quinoxaline-5,10-dioxide is a typical embodiment, are prepared from the appropriate 3aminoquinoxaline-1,4-dioxide-2-amidine and phosgene or an alkyl chloroformate followed by treatment with base.

United States Patent Seng et a1.

[ Feb. 4, 1975 COMPOSITIONS CONTAINING A QUINOXALINE-5,10-DIOXIDE AND METHOD OF USING SAME [75] Inventors: Florin Seng, Cologne; Kurt Ley,

Odenthal-Globusch; Karl Georg Metzger, Wuppertal-Elberfeld, all of Germany [73] Assignee: Bayer Aktiengesellschaft [22] Filed: June 11, 1973 [21] Appl. N0.: 368,477

Related U.S. Application Data [62] Division of sei. No. 249,702, May 2, 1972, Pat. No.

[30] Foreign Application Priority Data May 7, 1971 Germany 2122571 [52] U.S. Cl. 424/248, 424/250 [51] Int. Cl A6lk 27/00 Primary Examiner-Sam Rosen 57 Y ABSTRACT l,2-dihydro-2-oxo-4-aminopyrimido[4,5-b]quinoxaline-5,10-dioxides demonstrate antimicrobial activity and can be used as such or in compositions for combatting infections and in improving feed efficiency.

The compounds, of which 1,2-dihydro-2-oxo-4- dimethylarninopyrimido[4,5-b]quinoxa1ine-5,l0-

dioxide is a typical embodiment, are prepared from the appropriate 3-aminoquinoxaline-1,4-dioxide 2- amidine and phosgene or an alkyl chloroformate followed by treatment with base.

21 Claims, N0 Drawings COMPOSITIONS CONTAINING A ,QUINOXALlNE-5,10-DIOXIDE AND METHOD OF USING SAME This is a Divisional of Applicants copending application Ser. No. 249,702 filed May 2, 1972 now US. Pat.v

No. 3,8l4,756.

The present invention pertains to l,2-dihydro-2-oxo- 4-aminopy,rimido[4,5-blquinoxaline-S,lO-dioxides, to methods for the preparation and use of these com- I pounds, and to compositions adapted to the utilization wherein each of R and'R independent of the other is lower alkyl or (lower alkoxy)lower alkyl or R and R I together with the nitrogen atom to which they are attached are pyrrolidino, piperidino, hexamethyleneimino or morpholino', and a pharmaceutically neopentyl, tert.pentyl, hexyl, isohexyl, heptyl, octyl,

nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, and the like.

The term lower alkyl denotes a univalent saturated branched or straight hydrocarbon chain containing from 1 to 6 carbon atoms. Representative ofsuch lower alkyl groups are thus methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec.butyl, tert.butyl, pentyl, isopentyl, neopentyl, tert.pentyl, vhexyl, and the like.

The term lower alkoxy denotes a straight or branched hydrocarbon chain bound to the remainder of the molecule through an ethereal oxygen atom as, forexample, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, pentoxy and hexoxy. I

As indicated, the present invention also pertains to the physiologically acceptable non-toxic acid addition Formula I. In particular, the 1,2-dihydro-2-oxo-4- aminopyrimido[4,5-b]quinoxalines of- Formula I are obtained through treatment of an amidine of the formula:

g e 1 N cwherein R and R are as herein defined with phosgene or lower alkyl chloroforr nate and treating the product thereby formed with an organic or inorganic base.

The initial reaction between the amidines of the Formula II and the alkyl chloroformate or phosgene is carried out at temperatures of between about 20C and about 100C, preferably about 60C to about 80C, at normal or elevated pressure, generally normal pressure. At least about 1 mol of phosgene or alkyl chloroformate is employed per mol of amidine and preferably 1 to 10 mols of phosgene or 1 to 2 mols of alkyl chloroformate. Suitable diluents for the reaction include all denotes a univalent saturated salts of these basic compounds. Such salts include those 1 g R2 I o\./ T l I mmic1 ply III

in which R and R are as defined above. Under the action of an organic or inorganic base, the intermediate of Formula III is converted into thecompound of Formula I. The intermediate of Formula lll can be either isolated as for example by filtration, before being reacted with a base, or reacted directly with a base without isolation. Suitable organic bases include primary,

.secondary and tertiary amines, such as aliphatic, cycloaliphatic, aromatic, araliphatic, primary, secondary and tertiary amines such as methylamine, dimethylam ine, triethylamine, piperidine, pyridine, and the like. Inorganic bases include alkali metal hydroxides and alkaline earth metal hydroxides, alkali metal carbonates 'water, a polar organic solvent or a mixture thereof,

preferably a lower alkanol as for example methanol, ethanol, nand iso-propanol, n-, isoand tert.butanol and about 1 mol of the base is then added.

If the intermediate is treated with base without isolation, it is advisableto first remove any excess phosgene which may still be present in the reaction mixture. This can be accomplished for example simply by warming or aeration. The mixture is then treated with water or a polar organic solvent, preferably about the same amount of water as organic solvent and about 1 mol of the base is added per mol of the amidine originally employed.

In either'case, the treatment of the intermediate with the base is carried out at temperatures of from about lC to about 50C, preferably C to 30C. The product is isolated by any suitable method, for example by filtration.

respiratory tracts in poultry, especially in chicks, and mastitis of cows can be mentioned as particularly responsive to such treatment.

age and condition of the recipient of the treatment and the method of administration and dosage regimen. Generally, however, a suitable response is observed with doses of from 5 to 200 mg/kg of body weight. This of course must be adjusted to the individual case, utilizing sound professionaljudgment and careful observation of the response obtained. I

As representative of the spectrum of antimicrobial activity for these compounds, the following minimum inhibitory concentrations may be noted:

Minimum Inhibitory Concentration (MIC) in 'y/ml of Nutrient Medium Staphylo- Compound Slreplo- Est'luriz'ltiu Pseudmm (IV/H101," Acrunmnux m Ex- CUL'CUS cot-cits c011 mus tteruvulgaris I liqttt'fat'imu ample No. pyoge uureus ginosa nes W Flensungen N l4 A 261 Bonn N l K ll) 8085 l 0.6 2.5 1.25 2.5 100 100 1.25 10 5 2 1,25 1.25 5 l0 100 2.5 H) 2.5 l 5 l0 l5 l0() I00 100 I00 100 I0 6 .l0 5 l0 100 l5 '15 l Clustridium Alkali- Pusleu- Burdelella Mycuplusmue: .Ietuni bolugenes rella bronchi gullisephmirhine grunt:- It'nunt' fuecalis' mulmcidu seplica ticmn MS S6 [drum l 100 0.] l 1 l0 10 10 0,l 2 0.l l 100 0] 10 '1 l0. 01 5 100 H] 100 I0 100 100 IOU l0 6 lOO 0.l l l l0 l0 l0 (),l

The amidines of Formula II can be obtained in any suitable manner, for example by reaction of 2-amino-3- cyano-quinoxaline-di-N-oxide with a secondary amine in the presence of an inert organic solvent at C to 100C; see, e.g., British Patent Specification No. l,l70,387.

These products, both the free bases and their salts, display antibacterial activity against a variety of Gram positive and Gram negative bacteria such as Enterobacteriaceae, for example Escherichiae, especially Escherichia coli; Proteae as for example Proteus vulgaris, Proteus mirabilis, Proteus morganii' and Proteus rettgeri; Klebsiella as for example Klebsiella pneum0niae;- Salmonelleae; Pseudomonodaceae as for example Pseudomonas aerugt'nosa; Cocci, especially Staphylococci, such as for example Staphylococcus aureus; Streptococci as for example Streptococcus pyogenes; Enterococci as-for example Streptococcus faecalis; and Mycoplasma as for example Mycoplasma pneumoniae and Mycoplasma hominis. As a result ofthisactivity and their low toxicity, the compounds are useful in human and veterinary medicine in the treatment of infections in animals caused by Gram positive and Gram negative bacteria and by mycoplasma. Infections of the refer to physically discrete units'to be administered in single or multiple dosage to animals, each unit containing a predetermined quantity of active material in association with the required diluent, carrier or vehicle. The quantity of active material is that calculated to produce the desired therapeutic effect upon administration of one or more of such units.

Powders are prepared by comminuting the compound to a suitable fine size and mixing with a similarly comminuted diluent pharmaceutical carrier such as an edible carbohydrate material as for example, starch. Sweetening, flavoring, preservative, dispersing and coloring agents can also be present,

Capsules are made by preparing a powder mixture as described above and filling formed gelatin sheaths. A lubricant such as talc, magnesium stearate and calcium stearate can be added to the powder mixture as an ad juvant before the filling operation; a glidant such as colloidal silica may be added to improve flow properties; a disintegrating or solubilizing agent may be added to improve the availability of the medicament when the capsule is ingested.

Tablets are made by preparing a powder mixture, granulating or slugging, adding a lubricant and disintegrant and pressing into tablets. A powder mixture is prepared by mixing the compound, suitably comminuted, with a diluent or base such as starch, sucrose, kaolin, dicalcium phosphate and the like. The powder mixture can be granulated by wetting with a binder such as syrup, starch paste, acacia mucilage or solutions of cellulosic or polymeric materials and forcing through a screen. As an alternative to granulating, the powder mixture can be run through the tablet machine and the resulting imperfectly formed slugs broken into granules. The granules can be lubricated to prevent sticking to the tablet forming dies by means of the addition of stearic acid, a stearate salt, talc or mineral oil. The lubricated mixture is then compressed into tablets. The medicaments can also be combined with free flowing inert carriers and compressed into tablets directly without going through the granulating or slugging steps. A protective coating consisting ofa sealing coat of shellac, a coating of sugar or polymeric material and a polish coating of wax can be provided. Dyestuffs can be added tothese coatings to distinguish different unit dosages.

Oral fluids such as syrups and elixirs can be prepared in unit dosage form so that a given quantity,-c.g., a teaspoonful, contains a predetermined amount of thecompound. Syrups can be prepared by dissolving the compound in a suitably flavored aqueous sucrose solution while elixirs are prepared through the use ofa nontoxic alcoholic vehicle.-Suspensions can be formulated by dispersing the compound in a non-toxic vehicle in which it is insoluble.

Fluid unit dosage forms for parenteral administration can be prepared by suspending or dissolving a measured amount of the compound in a non-toxic liquid vehicle suitable for injection such as an aqueous or oleaginous medium and sterilizing the suspension or solution. Alternatively a measured amount of the compound is placed in a vial and the vial and its contents are sterilized and sealed. An accompanying vial or vehicle can be provided for mixing prior to administration.

In addition to their therapeutic use, the new compounds can also be used to promote the growth and improve feed utilization in animals, especially in raising young animals and fat-stock animals, as for example, calves, piglets and chicks.

Thecompounds can be administered in the feedstuff, in special feedstuff preparations, in preparations containing vitamins and/or mineral salts, or in the drinking water. Such administration of the compounds permits prevention or treatment of infections caused by Gram negative and by Gram positive bacteria and by mycoplasma, and additionally contributes to a more rapid growth of the animals and to'better feedefficiency. In this embodiment, the compounds are preferably mixed into the feedstuff or the drinking water in a concentration of l to 100 ppm.

The following examples will serve to further typify the nature of the present invention without being a limitation on the scope thereof:

EXAMPLE 1 product is filtered off, suspended in 150 ml of ethanol and treated with 10 g of triethylamine. This results in a red-violet solution, from which red crystals of 1,2-' dihydro-2-oxo-4 dimethylaminopyrimido[4,5-

b]quinoxaline-5,lO-dioxide' separate after some time.

Yield; 26 g (95%). melting point: 227C Analysis: C H N Q', (273) Calculated: C 52.7% H 4.0% N 253% Found: C 52.4% H 4.5% N 25.0%

EXAMPLE 2 14.3 g (0.05 mol) of 2-piperidinocarbimido-3- aminoquinoxaline-l,4-dioxidein 150 ml of chlorobenzene, are stirred with 6.5 g of chloroformic acid methyl ester for 8 hours at C. Thereafter the resulting intermediate product is filtered off and dissolved in dilute sodium hydroxide solution. On acidification with acetic acid, 9 g (58 percent of theory) of 1,2-dihydro-2-oxo- 4-piperidino-pyrimido[4,5-b]quinoxaline-5,lO-dioxide are obtained as red crystals which after boiling with alcohol melt at 264C.

I Analysis: C, H, N 0

Calculated: C 57.5% H 4.8% N 22.3% Found: C 57.5% H 5.2% N 22.1%

Similar results are obtained through the use of an equivalent amount of ethyl chloroforma'teh EXAMPLES 3-6 Utilizing equivalent amounts of 3-aminoquinoxalinel,4-dioxide-2-diethylamidine; Z-pyrrolidinocarbimido- 3-aminoquinoxaline-l ,4-dioxide; 2- morpholinocarbimido-3-aminoquinoxaline-l ,4-dioxide and 2-hexamethyleneiminocarbimido-3- aminoquinoxaline-l ,4-dioxide, respectively, the following compounds are obtained:

What is claimed is:

1. An antimicrobial composition comprising an antimicrobially effective amount of a compound selected from the group consisting of a 1,2-dihydro-2-oXo-4- aminopyrimido[4,5-b]quinoxaline-5,lO-dioxide of the formula: I I

wherein each of R and R independent of the other is lower alkyl of l to 6 carbon atoms or (lower alkoxy)- lower alkyl in which lower alkyl contains 1 to 6 carbon atoms and lower alkoxy contains 1 to 6 carbon atoms or R and R together with the nitrogen atom to which they are attached are pyrrolidino, piperidino, hexamethyleneimino or morpholino; and a pharmaceutically acceptable acid addition salt thereof and an inert pharmaceutical carrier. j

2. A composition according to claim 1 wherein said compound is l ,2-dihydro-2-oxo-4- dimethylaminopyrimido[4,5-b1quinoxaline-5,lO- dioxide.

3. A composition according to claim 1 wherein said compound is 1.2-dihydro-2-oxo-4- diethylaminopyrimido[4,5-b]quinoxaline-5,lO-dioxide.

o N/ v wherein each of R and R independent of the other is lower alkyl of l to 6 carbon atoms or (lower alkoxy)- lower alkyl in which lower alkyl contains l to 6 carbon atoms and lower alkoxy contains 1 to 6 carbon atoms or R and R together with the nitrogen atom to which they are attached are pyrrolidino, piperidino,

hexamethyleneimino or morpholino; and a pharmaceutically acceptable acid addition salt thereofin combination with a livestock feedstuff.

9. The composition of claim 8 wherein the compound is present in the amount of l to ppm.

10. The method of combatting microbial infectionin an animal which comprises administering to said animal an antimicrobially effective amount of a compound selected from the group consisting of a'LZ-dihydro-Z- oxo-4-aminopyrimido[4,5-b1quinoxaline-5,l 0-dioxide of the formula:

R17 .R? o \N/ wherein each of R and R independent of the other is lower alkyl of 1 to 6 carbon atoms or (lower alkoxy)- lower alkyl in which lower alkyl" contains 1 to 6 carbon atoms and lower alkoxy" contains l to 6 carbon atoms or R and R together with the nitrogen atom to which they are attached are pyrrolidino, piperidino, hexamethyleneiminoor morpholine; and a pharmaceutically acceptable acid addition salt thereof.

11. The methodof claim 10 wherein the compound is present in the amount of from about 5 to 200 mg/kg of body weight.

12. The method of claim wherein the compound is 1,2-dihydro-2-oxo-4-dimethylaminopyrimido[4,5- b]quinoxaline-5,lO-dioxide.

13. The method of claim 10 wherein the compound 1,2-dihydro-2-oxo-4-morpholinopyrimidol4,5-

20. A method for promoting growth inanimals which comprises feeding to said animal a growth promoting amount of a compound selected from the group consisting of a l,2 dihydro-2-oxo-4-aminopyrimido[4,5- b]quinoxaline-5,lO-dioxide of the formula:

\ri I wherein each of R and R independent of the other is lower alkyl of l to 6 carbon atoms or (lower alkoxy)- lower alkyl in which lower alkyl contains 1 to 6 carbon atoms and lower alkoxy" contains 1 to 6 carbon atoms or R and R together with the nitrogen atom to which they are attached are pyrrolidino, piperidino hexamethyleneimino or morpholinojand a pharmaceutically acceptable acid addition salt thereof in combination with a livestock feedstuff.

21. The method of claim 20 wherein the compound is present in the amount of l to 100 ppm. 

1. AN ANTIMICROBIAL COMPOSITION COMPRISING AN ANTIMICROBIALLY EFFECTIVE AMOUNT OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF A 1,2-DIHYDRO-2-OXO-4-AMINOPYRIMIDO(4,5B)QUINOXALINE-5,10-DIOXIDE OF THE FORMULA:
 2. A composition according to claim 1 wherein said compound is 1,2-dihydro-2-oxo-4-dimethylaminopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 3. A composition according to claim 1 wherein said compound is 1,2-dihydro-2-oxo-4-diethylaminopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 4. A composition according to claim 1 wherein said compound is 1,2-dihydro-2-oxo-4-piperidinopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 5. A composition according to claim 1 wherein said compound is 1,2-dihydro-2-oxo-4-pyrrolidinopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 6. A composition according to claim 1 wherein said compound is 1,2-dihydro-2-oxo-4-morpholinopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 7. A composition according to claim 1 wherein said compound is 1,2-dihydro-2-oxo-4-hexamethyleneiminopyrimido(4,5-b)quinoxaline-5,10 -dioxide.
 8. A chemotherapeutic and growth promoting feed composition comprising an effective amount of a compound selected from the group consisting of a 1,2-dihydro-2-oxo-4-aminopyrimido(4,5-b)quinoxaline-5,10-dioxide of the formula:
 9. The composition of claim 8 wherein the compound is present in the amount of 1 to 100 ppm.
 10. The method of combatting microbial infection in an animal which comprises administering to said animal an antimicrobially effective amount of a compound selected from the group consisting of a 1,2-dihydro-2-oxo-4-aminopyrimido(4,5-b)quinoxaline-5,10-dioxide of the formula:
 11. The method of claim 10 wherein the compound is present in the amount of from about 5 to 200 mg/kg of body weight.
 12. The method of claim 10 wherein the compound is 1,2-dihydro-2-oxo-4-dimethylaminopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 13. The method of claim 10 wherein the compound is 1,2-dihydro-2-oxo-4-diethylaminopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 14. The method of claim 10 wherein the compound is 1,2-dihydro-2-oxo-4-piperidinopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 15. The method of claim 10 wherein the compound is 1,2-dihydro-2-oxo-4-pyrrolidinopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 16. The method of claim 10 wherein the compound is 1,2-dihydro-2-oxo-4-morpholinopyrimido(4,5-b)quinoxaline-5,10-dioxide.
 17. The method of claim 10 wherein the compound is 1,2-dihydro-2-oxo-4-hexamethyleneiminopyrimido(4,5-b)quinoxaline-5,10 -dioxide.
 18. The method of claim 10 in which the composition is administered orally.
 19. The method of claim 10 in which the composition is administered parenterally.
 20. A method for promoting growth in animals which comprises feeding to said animal a growth promoting amount of a compound selected from the group consisting of a 1,2-dihydro-2-oxo-4-aminopyrimido(4,5-b)quinoxaline-5,10-dioxide of the formula:
 21. The method of claim 20 wherein the compound is present in the amount of 1 to 100 ppm. 